Tim Tszyu entered fight week of the belief this would be his final appearance in Australia before embarking on a world title run.

The rising junior middleweight contender fought accordingly, having his way with late replacement Stevie Spark whom Tszyu annihilated in rounds. A pair of knockdowns by Tszyu prompted the stoppage at 2:22 of round three Wednesday evening at Newcastle Entertainment Centre in Newcastle, Australia.

Spark became an instant favorite with the local media after agreeing to the fight on short notice, replacing Michael Zerafa on seven days’ notice. Insisting that he was here to win and not just “make up the numbers,” Spark fought accordingly in the opening round.

A right hand managed to get through for the 24-year-old Toowoomba native, who was fighting at junior middleweight for the first time after having only recently moved up from junior welterweight. Spark managed an uppercut on the inside, which Tszyu brushed past as he settled into a groove near the close of round one.

Tszyu found his rhythm in round two, walking through a right hand to slam home a left hook as Spark was pinned along the ropes. An uppercut snapped back the head of Spark, whose offense suddenly shut down as Tszyu continued on the attack.

Spark was forced to contend with swelling under his right eye along with a heavily favored opponent who clearly hit his stride. His corner acted accordingly, buying some time after a bucket of ice in their corner mysteriously tipped over and spilled into center ring.

The stall tactic merely prolonged the inevitable.

Tszyu began to target Spark’s midsection, which proved key in closing the show. A left hook to the body produced the bout’s first knockdown, with Spark showing worse for the wear with more than a minute to go in the round. He wouldn’t come close to hearing the bell, as another left hook sent him to the canvas. The second knockdown and subsequent reaction was enough for referee Brad Vocale to immediately halt the contest.

Spark falls to 12-2 (11KOs) in defeat, snapping an eleven-fight win streak. His lone other career loss came in his second pro fight, going on to score ten consecutive knockouts before earning an eight-round, unanimous decision victory over Jack Brubaker this past April in Wollongong, Australia.

Tszyu will now set his sights on the junior middleweight elite. The unbeaten contender—who improves to 19-0 (15KOs)—is ranked number-one by the World Boxing Organization (WBO), whose current titlist Brian Castaño (17-0-1, 12KOs) is set to face lineal/WBC/WBA/IBF champ Jermell Charlo in an undisputed junior middleweight clash July 17 stateside in San Antonio, Texas.

It's obviously a long wait to get to that stage even as the number-one contender for at least one belt. Tszyu is willing to further earn his place at the table. 

"There Liam Smith, [Magomed] Kurbanov and Danny Garcia—those are the three boys I'm going for," Tszyu said after scoring his fifth consecutive knockout. "If you're watching boys, I'm coming for you."

The bout aired live on Main Event Pay-Per-View in Australia and ESPN+ in the United States.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox